Cooling fan blowback control valve, hydraulic system and engineering machinery

Abstract

The utility model discloses a heat dissipation fan blowback control valve, a hydraulic system and engineering machinery, and the heat dissipation fan blowback control valve comprises an inlet P used for being connected with an outlet of an oil pump; the auxiliary port P1 is used for being connected with an existing hydraulic pipeline or an oil tank which is originally connected with an oil pump outlet; the working port A is used for being connected with a reverse blowing control port of a cooling fan; the inlet P is respectively connected with the inlet of the logic valve and the inlet of the pressure reducing valve; an outlet of the logic valve is connected with the auxiliary port P1; an outlet of the reducing valve is connected with an inlet of the reversing valve through a damping hole; an outlet II of the reversing valve is connected with the working port A and a control port of the logic valve. The utility model can be flexibly matched with a hydraulic system, especially in the occasion that the hydraulic system has been determined and has no redundant oil pump, but the fan blowback function needs to be added, and the production and modification cost is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of engineering machinery technology, specifically relating to a cooling fan backflush control valve, a hydraulic system, and engineering machinery. Background Technology

[0002] In agricultural machinery, reverse-flow cooling fans ensure that the radiator does not become clogged, especially in dusty working environments such as construction machinery and vehicles. The fan, hydraulically controlled, can change its airflow direction at any time, thereby cleaning the radiator and preventing reduced engine efficiency due to decreased cooling performance.

[0003] Existing cooling fan backflow control technology requires the addition of a hydraulic pump or causes hydraulic pump flow diversion. This increases costs and also increases the heat generated by the hydraulic system. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a cooling fan backflush control valve, a hydraulic system, and engineering machinery. The cooling fan backflush control valve can be flexibly matched with the hydraulic system, especially in situations where the hydraulic system is already fixed, there are no extra oil pumps, but the fan backflush function still needs to be added, thus reducing production and modification costs.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] In a first aspect, a cooling fan backflush control valve is provided, comprising: an inlet P for connection to the outlet of an oil pump; an auxiliary port P1 for connection to an existing hydraulic pipeline or oil tank originally connected to the outlet of the oil pump; a working port A for connection to the cooling fan backflush control port; the inlet P is connected to the inlet of a logic valve and the inlet of a pressure reducing valve respectively; the outlet of the logic valve is connected to the auxiliary port P1; the outlet of the pressure reducing valve is connected to the inlet of a directional valve through a damping orifice; and the outlet of the directional valve is connected to the working port A and the control port of the logic valve.

[0007] Furthermore, it also includes a return port T, with the return ports of the directional valve and the pressure reducing valve connected to the return port T respectively.

[0008] Furthermore, it also includes an overflow valve, with its inlet connected to inlet P and its outlet connected to return port T.

[0009] Furthermore, the directional valve is a two-position four-way directional valve, and the outlet of the directional valve is closed.

[0010] Furthermore, when the cooling fan is running normally, the directional valve is not energized and operates in the shut-off position; the inlet of the directional valve is connected to outlet one, and outlet two of the directional valve is connected to the return port of the directional valve; there is no feedback pressure at the control end of the logic valve, and the logic valve operates in the connected position; the hydraulic oil output by the oil pump flows through inlet P, logic valve, and auxiliary port P1 into the existing hydraulic pipeline or oil tank originally connected to the oil pump outlet.

[0011] Furthermore, when the cooling fan needs to backflush, the reversing valve is energized and operates in the connected position; the inlet of the reversing valve is connected to outlet two, and outlet one of the reversing valve is connected to the return port of the reversing valve. The control end of the logic valve has feedback pressure, and the logic valve operates in the connected position under the combined action of the control end pressure and the inlet pressure; after the hydraulic oil output by the oil pump flows into inlet P, part of it flows into the cooling fan backflush control port through the pressure reducing valve, damping orifice, reversing valve, and working port A, and the other part flows into the existing hydraulic pipeline or oil tank originally connected to the oil pump outlet through the logic valve and auxiliary port P1.

[0012] In a second aspect, a hydraulic system is provided, wherein the hydraulic system is configured with the cooling fan backflush control valve described in the first aspect.

[0013] Thirdly, an engineering machine is provided, which is equipped with the cooling fan backflush control valve described in the first aspect.

[0014] Compared with the prior art, the beneficial effects achieved by this utility model are as follows: This utility model connects the inlet P, which is connected to the oil pump outlet, to the inlet of the logic valve and the inlet of the pressure reducing valve respectively; the outlet of the logic valve is connected to the auxiliary port P1, which is used to connect to the existing hydraulic pipeline or oil tank originally connected to the oil pump outlet; the outlet of the pressure reducing valve is connected to the inlet of the directional valve through the damping hole; the outlet of the directional valve is connected to the working port A and the control port of the logic valve, and the working port A is used to connect to the cooling fan backflush control port; this realizes the flexible matching of the cooling fan backflush control valve with the hydraulic system, especially in the case where the hydraulic system is already determined, there is no spare oil pump, but the fan backflush function needs to be added, thus reducing production and modification costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the principle of a cooling fan backflush control valve provided in an embodiment of this utility model;

[0016] In the diagram: 1. Relief valve; 2. Logic valve; 3. Pressure reducing valve; 4. Damping orifice; 5. Directional control valve. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0018] Example 1

[0019] like Figure 1 As shown, a cooling fan backflush control valve includes: an inlet P for connecting to the outlet of an oil pump, an auxiliary port P1 for connecting to an existing hydraulic pipeline or oil tank originally connected to the outlet of the oil pump, a working port A for connecting to the cooling fan backflush control port, a return port T, an overflow valve 1, a logic valve 2, a pressure reducing valve 3, a damping orifice 4, and a reversing valve 5.

[0020] The inlet P is connected to the inlet of logic valve 2 and the inlet P3 of pressure reducing valve 3 respectively; the outlet of logic valve 2 is connected to auxiliary port P1; the outlet A3 of pressure reducing valve 3 is connected to the inlet P5 of directional valve 5 through damping hole 4; the outlet B5 of directional valve 5 is connected to working port A and control port of logic valve 2.

[0021] The return port T5 of the reversing valve 5 and the return port T3 of the pressure reducing valve 3 are respectively connected to the return port T.

[0022] The inlet of relief valve 1 is connected to inlet P, and the outlet of relief valve 1 is connected to return port T.

[0023] The reversing valve 5 is a two-position four-way reversing valve, and the outlet of the reversing valve 5, A5, is closed.

[0024] 1. When there is no spare oil pump, the inlet P of the cooling fan backflush control valve is connected to the outlet of the oil pump, and the auxiliary port P1 is connected to the existing hydraulic pipeline that was originally connected to the outlet of the oil pump. That is, the cooling fan backflush control valve is connected in series to the hydraulic pipeline of the oil pump outlet through the inlet P and the auxiliary port P1.

[0025] (1) If the cooling fan is running normally, the reversing valve 5 is not energized and works in the cut-off position; the inlet P5 of the reversing valve 5 is connected to the outlet A5, the outlet B5 of the reversing valve 5 is connected to the return port T5 of the reversing valve 5, the control end of the logic valve 2 has no feedback pressure, and the logic valve 2 works in the connected position under the action of the inlet pressure; the hydraulic oil output by the oil pump flows into the existing hydraulic pipeline that is originally connected to the outlet of the oil pump through the inlet P, the logic valve 2, and the auxiliary port P1.

[0026] The relief valve 1 is initially closed. When the load of other working devices connected to the auxiliary port P1 increases until the pressure set by the relief valve 1 is reached, the relief valve 1 opens, and the hydraulic oil returns to the oil tank through the cooling fan backflow port T of the control valve.

[0027] Whether pressure reducing valve 3 is open depends on whether the other working device connected to auxiliary port P1 is functioning. If the other working device connected to auxiliary port P1 is in an unloaded state (working pressure is 0), the pressure at the inlet P3 and outlet A3 of pressure reducing valve 3 is equal, and its magnitude is equal to the initial set pressure of logic valve 2, 10 bar. At this time, pressure reducing valve 3 is in the normally open position. If the other working device connected to auxiliary port P1 is in a working state, the pressure at the inlet P3 of pressure reducing valve 3 is equal to the working pressure of the other working device connected to auxiliary port P1, and the pressure at the outlet A3 of pressure reducing valve 3 is equal to the set pressure of 40 bar. Pressure reducing valve 3 is in a state of frequent switching between opening and closing, so that the outlet A3 of pressure reducing valve 3 always maintains a pressure of 40 bar.

[0028] (2) When the cooling fan needs to backflush, the reversing valve 5 is energized and operates in the connected position; the inlet P5 of the reversing valve 5 is connected to the outlet B5, the outlet A5 of the reversing valve 5 is connected to the return port T5 of the reversing valve 5, the control end of the logic valve 2 has feedback pressure, and the logic valve 2 operates in the connected position under the combined action of the control port pressure and the inlet pressure; after the hydraulic oil output by the oil pump flows into the inlet P, part of it flows into the cooling fan backflush control port through the pressure reducing valve 3, the damping hole 4, the reversing valve 5, and the working port A, and the other part flows into the existing hydraulic pipeline that was originally connected to the oil pump outlet through the logic valve 2 and the auxiliary port P1.

[0029] The feedback pressure at the control end of logic valve 2 is equal to the set pressure of outlet A3 of pressure reducing valve 3, which is 40 bar. Under the action of the inlet pressure, logic valve 2 is in the connected position, and hydraulic oil flows through the outlet of logic valve 2 to auxiliary port P1. If other working devices connected to auxiliary port P1 are in an unloaded state or their working pressure is lower than 50 bar, the inlet pressure of logic valve 2 is equal to the control port pressure of logic valve 2 plus the initial set pressure of logic valve 2, which is 10 bar, i.e., the inlet pressure of logic valve 2 is 50 bar. If the working pressure of other functional working devices connected to auxiliary port P1 is higher than 50 bar, the inlet pressure of logic valve 2 is equal to the working pressure of the other working devices connected to auxiliary port P1. Regardless of whether other working devices connected to auxiliary port P1 are working, as long as the inlet pressure of logic valve 2 is ≥ 50 bar, pressure reducing valve 3 is in an open / closed switching state, ensuring that the outlet pressure A3 of pressure reducing valve 3 is stable at 40 bar.

[0030] 2. When there is an excess oil pump, the inlet P of the cooling fan backflush control valve is connected to the outlet of the "excess oil pump", and the auxiliary port P1 is connected to the oil tank.

[0031] (1) If the cooling fan is operating normally, the reversing valve 5 is not energized and operates in the cut-off position; the inlet P5 of the reversing valve 5 is connected to the outlet A5, and the outlet B5 of the reversing valve 5 is connected to the return port T5 of the reversing valve 5. There is no feedback pressure at the control end of the logic valve 2, and the logic valve 2 operates in the connected position under the action of the inlet pressure; the hydraulic oil output by the oil pump flows into the oil tank through the inlet P, the logic valve 2, and the auxiliary port P1. The inlet pressure of the logic valve 2 is the initial set pressure of 10 bar.

[0032] The relief valve 1 is initially in the closed state.

[0033] The pressure at the inlet P3 of the pressure reducing valve 3 is equal to the initial set pressure of logic valve 2, which is 10 bar. At this time, the pressure reducing valve 3 is in the normally open position.

[0034] (2) When the cooling fan needs to backflush, the reversing valve 5 is energized and operates in the connected position; the inlet P5 of the reversing valve 5 is connected to the outlet B5, the outlet A5 of the reversing valve 5 is connected to the return port T5 of the reversing valve 5, the control end of the logic valve 2 has feedback pressure, and the logic valve 2 operates in the connected position under the combined action of the control port pressure and the inlet pressure; after the hydraulic oil output by the oil pump flows into the inlet P, part of it flows into the cooling fan backflush control port through the pressure reducing valve 3, the damping hole 4, the reversing valve 5, and the working port A, and the other part flows into the oil tank through the logic valve 2 and the auxiliary port P1.

[0035] The hydraulic oil output by the oil pump flows into the cooling fan backflush control port through inlet P, pressure reducing valve 3, damping orifice 4, reversing valve 5, and working port A.

[0036] The feedback pressure at the control end of logic valve 2 is equal to the set pressure of outlet A3 of pressure reducing valve 3, which is 40 bar. Under the influence of the inlet pressure, logic valve 2 operates in the connected position, and hydraulic oil returns to the oil tank through the outlet of logic valve 2 to the auxiliary port P1. The inlet pressure of logic valve 2 is equal to the pressure at the control port of logic valve 2 plus the initial set pressure of logic valve 2, which is 10 bar, i.e., the inlet pressure of logic valve 2 is 50 bar. Pressure reducing valve 3 is in an open / closed switching state, ensuring that the outlet pressure A3 of pressure reducing valve 3 remains stable at 40 bar.

[0037] In this invention, the pressure of the overflow valve and the pressure reducing valve can be adjusted according to actual needs. Through electronic control, the fan can be switched to reverse blowing within specific time periods, and the duration of the reverse blowing can be controlled. This invention allows technicians to flexibly match hydraulic systems, especially in situations where the hydraulic system is already fixed, there are no spare pumps, but a fan reverse blowing function needs to be added, thus reducing production and modification costs.

[0038] Example 2

[0039] Based on the cooling fan backflush control valve described in Embodiment 1, this embodiment provides a hydraulic system equipped with the cooling fan backflush control valve described in Embodiment 1.

[0040] Example 3

[0041] Based on the cooling fan backflush control valve described in Embodiment 1 and the hydraulic system described in Embodiment 2, this embodiment provides an engineering machinery, which is equipped with either the cooling fan backflush control valve described in Embodiment 1 or the hydraulic system described in Embodiment 2.

[0042] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A heat dissipation fan back-blow control valve characterized by, Comprise: An inlet P for connecting with the outlet of the oil pump; An auxiliary port P1 for connecting with the existing hydraulic pipeline or oil tank originally connected with the outlet of the oil pump; A working port A for connecting with the back-blowing control port of the cooling fan; The inlet P is connected with the inlet of the logic valve (2) and the inlet of the pressure reducing valve (3) respectively; The outlet of the logic valve (2) is connected with the auxiliary port P1; The outlet of the pressure reducing valve (3) is connected with the inlet of the reversing valve (5) through the damping hole (4); The outlet two of the reversing valve (5) is connected with the working port A and the control port of the logic valve (2).

2. The heat-dissipating fan backwash control valve according to claim 1, characterized in that, Further comprising a return port T, the return port of the reversing valve (5) and the return port of the pressure reducing valve (3) are connected with the return port T respectively.

3. The heat-dissipating fan backwash control valve according to claim 2, characterized in that, Further comprising an overflow valve (1), the inlet of the overflow valve (1) is connected with the inlet P, and the outlet of the overflow valve (1) is connected with the return port T.

4. The heat-dissipating fan backwash control valve according to claim 3, characterized in that, The reversing valve (5) is a two-position four-way reversing valve, and the outlet one of the reversing valve (5) is closed.

5. The heat-dissipating fan backwash control valve according to claim 4, characterized in that, When the cooling fan operates normally, the reversing valve (5) is not powered and works in the closed position; the inlet of the reversing valve (5) is connected with the outlet one, the outlet two of the reversing valve (5) is connected with the return port of the reversing valve (5), and the control end of the logic valve (2) has no feedback pressure, so that the logic valve (2) works in the connected position; the hydraulic oil output by the oil pump flows into the existing hydraulic pipeline or oil tank originally connected with the outlet of the oil pump through the inlet P, the logic valve (2) and the auxiliary port P1.

6. The heat-dissipating fan backwash control valve according to claim 4, wherein, When the cooling fan needs back-blowing, the reversing valve (5) is powered and works in the connected position; the inlet of the reversing valve (5) is connected with the outlet two, the outlet one of the reversing valve (5) is connected with the return port of the reversing valve (5), the control end of the logic valve (2) has feedback pressure, and the logic valve (2) works in the connected position under the joint action of the control end pressure and the inlet pressure; the hydraulic oil output by the oil pump flows into the inlet P, part of the hydraulic oil flows into the back-blowing control port of the cooling fan through the pressure reducing valve (3), the damping hole (4), the reversing valve (5) and the working port A, and the other part of the hydraulic oil flows into the existing hydraulic pipeline or oil tank originally connected with the outlet of the oil pump through the logic valve (2) and the auxiliary port P1.

7. A hydraulic system characterized by, The hydraulic system is provided with the back-blowing control valve of the cooling fan according to any one of claims 1-6.

8. A working machine, characterized in that The engineering machinery is provided with the back-blowing control valve of the cooling fan according to any one of claims 1-6.

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